intel-iommu: Use correct domain ID when caching mode is enabled

In caching-mode mappings of pages (changes from non-present to present)
require invalidation.
Currently, this IOTLB flush is performed with domain ID of zero.
This is not according to the VT-d spec and causes big problems for
emulating software.
This patch uses the correct domain ID in IOTLB flushes.
Device IOTLB invalidation is performed only on present to non-present
changes. This decision is now based on explicit parameter instead of
zero domain-ID.

Signed-off-by: Nadav Amit <nadav.amit@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

diff --cc drivers/pci/intel-iommu.c
Simple merge